The present invention relates to a diaphragm valve arrangement.
Diaphragm valves are known. Such a valve arrangement generally comprises a flexible diaphragm which actuates a member depending upon the pressures which exist on the opposite sides of the diaphragm. Thus, it will be readily appreciated that it is very important that the diaphragm, which is clamped at its outer region between two juxtaposed clamping members so as to seal the pressure compartments existing on opposite sides of the diaphragm and so as to thereby prevent pressure from leaking past the latter, be fully functional even after having been assembled in the valve arrangement for long periods of time.
In the prior art, the rubber material of the diaphragm located in its clamped portion has a tendency to flow. Thus, over time, the sealing capability of the diaphragm will worsen and gradually deteriorate so that eventually the entire valve arrangement will be inoperative. This time period is shortened in those cases where the diaphragm is subjected to elevated temperatures and pressures.